1. Field of the Invention
The invention relates to an occupant protection apparatus for a vehicle, and more particularly, relates to an occupant protection apparatus which is mounted in a vehicle such as an automobile and which restrains the lower limbs of an occupant in the case of a collision.
2. Description of the Related Art
Examples of an occupant protection apparatus for a vehicle that is mounted in a vehicle like an automobile are known, such as the configuration disclosed in Japanese Patent No. 2679405. In this configuration, a first protector (also referred to as an “active knee bolster”) and a second protector (also referred to as an “active knee bolster”) are movably supported by a vehicle body. In the case that deceleration of the vehicle exceeds a predetermined value, the first and second protectors are operated by a first and second actuator so as to support lower limbs of the occupant from a vehicle forward direction. At the same time, a front portion of a seat cushion separates from a rear portion thereof, such that the front portion moves in the vehicle forward direction.
However, with art of this type, when a frontal collision of the vehicle occurs, following contact of the active knee bolsters and the lower limbs, a portion of the active knee bolsters that restrains the lower limbs (a knee area) of the occupant is moved in the direction of the lower limbs of the occupant with a substantial movement force capable of restraining the lower limbs. As a result, in particular, in the case that the active knee bolsters come into contact with the lower limbs of an occupant of large build, it is necessary from the point of view of protecting the lower limbs of the occupant at the time of contact to reduce the aforementioned movement force. However, if the movement force is reduced, the restraining force is also reduced, and the likelihood that the lower limbs will be restrained is decreased.